This guy has had zero success at the major league level in numerous tries, but AAA depth never hurts I guess.

That really isn't true. He pitched three shutout innings against the Tigers in a come-from-behind White Sox win in May, holding the Tigers while the White Sox were coming back to give him their last win against Detroit for a huge chunk of the season. He also pitched three shutout innings in relief against the Twins after that. Between those games, he gave up ninth-inning home runs to the Cubs in a game where the White Sox had a 7-0 lead. His ERA was below 3 before he finished the win against the Cubs. It balooned after that, and his two starts with the Red Sox yielded an ERA of 22.24.

Stewart hasn't had any consistent success as a starter. He has had limited and inconsistent success as a reliever. The White Sox will probaby have better pitchers in both the rotation and the bullpen in 2013, but there will be worse pitchers in the major leagues, probably in both roles.

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The very existence of flamethrowers proves that some time, somewhere, someone said to themselves, "You know, I want to set those people over there on fire, but I'm just not close enough to get the job done." -George Carlin

That really isn't true. He pitched three shutout innings against the Tigers in a come-from-behind White Sox win in May, holding the Tigers while the White Sox were coming back to give him their last win against Detroit for a huge chunk of the season. He also pitched three shutout innings in relief against the Twins after that. Between those games, he gave up ninth-inning home runs to the Cubs in a game where the White Sox had a 7-0 lead. His ERA was below 3 before he finished the win against the Cubs. It balooned after that, and his two starts with the Red Sox yielded an ERA of 22.24.

Stewart hasn't had any consistent success as a starter. He has had limited and inconsistent success as a reliever. The White Sox will probaby have better pitchers in both the rotation and the bullpen in 2013, but there will be worse pitchers in the major leagues, probably in both roles.

Didn't he get rocked by the Cubs in a Start last season and then pretty much get sent to the minors right after the game?